This 85xt I've been working on has 2 problems when lowering the loader from the raised position. 1, bucket control becomes erratic, almost like it has a broken spool centering spring. 2, when lowering loader from raised position, it pulls down on the engine. Almost like it's fighting itself. Last summer, I serviced it for the 1st time. Drained water contaminated hydraulic oil out of the tank and replaced the filters. At the time I wasn't aware of this problem so I didn't examine the contents of the filters. So far, I've replaced the counter balance valve. This made the controls more responsive and gave boom and bucket control (although slow) only at max rpm. I then changed the equipment pump. Them pump is clearly worn by looking at the gears. Same thing only now it'll have some control at 1/2 throttle and above. This machine has 1329 hours on it. :Banghead
Had similar issue on one. The spool was broken in the control valve (unit used to work at a chemical plant, lots of rust), so replaced control valve. Also had loading of engine when lowering. The self leveling was not working properly, so sent power to solenoid, and it stopped loading the engine on boom down. So here is my suggestions 1. Send power to the self leveling solenoid and see if the boom will lower without loading the engine. 2. Removed the endcaps on the control valve, and inspect the spools. Good luck.
Thank you. I pulled out both spools 1st. I thought it was a spool centering problem. Springs, seals, solenoids, all checked out. Evidence of water damage on the counter balance valve (a non-servicable part), replaced it too. I was able to get in contact with an old friend of mine, a road mechanic you know, he at 1st thought it sounded like a cracked valve body. He had the manual with schematics. With that, we where able to narrow the problem down to the spool in the self leveling valve is damaged, or a plugged orifice that controls that spool movement. I haven't jumped in yet, I will once I have the tech. manual. Thank you again, I'll keep you posted.